Combustion apparatus for a gas turbine of the reaction type



Jul 19, 1960 K. TYCHOTA COMBUSTION APPARATUS FOR A GAS TURBINE OF THE REACTION TYPE Filed Nov. 26, 1958 2 Sheets-Sheet 1 INVENTOR. KAZ/M/ERZ TVCHOTA ffM July 19, 1960 K. TYCHOTA 2,945,343

COMBUSTION APPARATUS FOR A GAS TURBINE OF THE REACTION TYPE Filed Nov. 26, 1958 2 Sheets-Sheet 2 INVENTOR. KAZ/M/ERZ TYCHOTA BY Z w ATTORNEY operations.

fooMBUsrroN APPARATUS FOR A GAS TURBINE on THE REACTION TYPE Kazimierz Tychota, City of Dusseldorf Consulate General,

Dusseldorf, Germany I Filed Nov. 26, 1958, Ser. No. 776,576 I 7 Claims. j(Cl. 60-3934) is burned in aplurality of rotating combustion chambers and. expands therefrom to impinge against a plurality of turbine buckets.

The term combustion apparatus of the intermittent combustion type refers to combustion chambers wherein theexhaustgases are discharged in discrete separate pulses. Typically, these combustion chambers include cylinders having reciprocating pistons operable therein for compressing a combustible mixture, valve means for directing the combustible mixture into and out of the cylinder, ignition means for igniting the combustible mixture, and timing means for coordinating the sequence of Heretofore, rotary combustion chambers of theintermittent .type have not proved to be completely satisfactory for operation with an exhaust gas turbine. hasfin part been due to the inherently adverse con-- ditionwhich exists due to the fact that a turbine operates most elficiently with a smooth supply of motive fluid whereas the intermittent type combustion chamber generally supplies exhaust gases in the form of a distinct series of pulses Additionally, prior forms of rotary intermittent combustion chambers have not been completely satisfactory since the combustion apparatus utilized resulted in the weight of the overallqengine being considerably higher than the weight of different forms of engines of comparable, horsepower. This of "necessity resulted in higher initial and subsequentoperating costs for. these engines. Another primary factor relating to the adverse reception of early types of intermittent rotary combustion chambers has been the relatively high temperatures involved in their operation and the difiiculty encountered in achieving low thermal stresses in both the turbine. and the combustion equipment.

j Accordingly, one object of my invention is to provide an irnproved rotary combustion chamber.

Anadditional .object of my invention is to provide a rotary combustion chamber which will supply exhaust gases to a gas turbine in a relatively smooth stream fo'refiicient operation of the gas turbine.

A,further object of my invention is to provide a rotary combustion chamber whose weight to horsepower ratio is considerably improved over that of prior arrangements. Another object of my invention is to provide a rotary combustion chamber which is capable of limiting the temperature of the exhaust gases leaving the combustion chamber.. 7

A still-further object ofrny invention is to provide a practical and. economical rotary combustion chamber for use I with -a gas turbine.

' Further objects and advantages of my invention will become apparent as the following description proceeds. Briefly stated, in accordance with one embodiment of my invention, I provide a cylinder carrying member mqunted for rotation about a central valve member. The 'valve member is formed with segment gears and cam means intermittently disposed about its peripheral portion and intake and exhaust ducts disposed about its central portion. Gear wheels and cam followers mounted on each cylinder cooperate with the intermittent segment gears and cams to cause controlled reciprocatory motion of the pistons located with each cylinder. The arrangement of parts is such that, upon rotation of the cylinder carrying member, intake ducts are disposed beneath the cylinder during the outward strokes of each piston due to the action of the segment gear and gear wheels, and exhaust ducts are gradually uncovered and disposed beneath the cylinders during a portion of the inward stroke of the piston due to the action of the cam means. The

segment gears, cams, intake, and exhaust ducts positioned on the valve member, cooperate to provide a great number of controlled exhaust pulses during each revolution of the cylinder carrying member. With this arrangement the number of exhaust pulses per revolution of the cylinder carrying member is equal to the number of cylinders on that member times the number of sets of inlet and exhaust ducts on the valve member, thereby achieving considerably improved weight to power ratio and a smoother stream of exhaust gas flow from the combustion chambers to the turbine.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which I regard as my invention, it is believed that theinvention will be better understood from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a side elevation view, partly in section, of a portion of an engine embodying my invention.

Fig. 2 is a top plan view, partly in section, of the combustion chamber arrangement shown in Fig. 1.

Fig. 3 is an end elevation view, partly in section, of one of the combustion chamber cylinders prior to the start of the intake cycle.

Fig. 4 is a partial side elevation view of the piston actuating cam and gear segments mounted on the valve member.

Fig. 5 is a top plan view of the intake ducting, exhaust ducting, and coolant introduction passageways on the valve member.

Fig. 6 is a sectional end elevation view taken along the line 6-6 of Fig. 5 which shows details of the intake and exhaust ducting and coolant introduction passageways.

Fig. 7 is a schematic end view of an engine incorporating my invention which shows means for drivingly connecting the rotary combustion chamber with the gas turbine rotor.

Referring to Fig. 1, there is shown one embodiment of my invention as applied to combustion apparatus wherein the cylinders. rotate about a stationary valve member andrthe exhaust gases are directed at a radial gas turbine located radially inwardly of the combustion chambers. In this arrangement the combustion apparatus includes a rotary cylindrical ring member 1 which carries a plurality of cylinders 2 mounted about its periphery in spaced apart relation. The cylinders may be either cast integrally with the ring member or mounted thereon by any wellknown means such as Welding or bolting. Each cylinder 2 contains a piston 3 reciprocably mounted therein for drawing in a combustible mixture on its intake stroke and compressing and discharging the exhaust gases on its discharge stroke. Ignition means comprising a spark plug 4 and its associated circuitry are utilized to ignite the mixture at a predetermined time during the compression and discharge stroke of the piston 3'. The spark plug 4 is mounted in an aperture 5 formed at the internal end of the cylinder 2.

As may be more clearly seen in Fig. 3, each cylinder 2 Patented July 19, 1960 has a crank 6 mounted thereon for controlled rotary motion. Additionally, each cylinder is provided with a closure plate 7 which forms a closed clearance space within which the crank may rotate. A connecting rod 8, connected at one end to the crank 6 and at its other end to the piston 3, cooperates with the crank and piston to convert the controlled rotary'motion of the crank to controlled reciprocating motion of the piston.

' In order to obtain controlled rotary motion of the crank 6, gear wheels 9 are mounted at each end of the crank externally of the cylinder 2. Each gear wheel 9 has a cam follower pin 10 formed thereon, the gear wheels and cam followers being arranged to cooperate with actuating means in a manner to be more fully described hereinafter.

Returning to Fig. l, a stationary cylindrical valve member is shown at 11. The valve member 111 includes a plurality of intake ducts, two of which are shown at 12 and 13, and a plurality of exhaust ducts, two of which are shown at 14 and 15, circumferentially spaced about its periphery. The valve member 11 and cylinder carrying ring member 1 are positioned closely adjacent to each other, the ring member being in tight sliding contact with the valve member, in order to be able to retain pressurized gases in the cylinders. It should be noted that, in this embodiment, the valve member 11 forms the internal end for each cylinder 2 and that, as the cylinder carrying ring member 1 rotatesabout the valve member 11, various inlet and exhaust ducts will progressively be uncovered and brought into communication with the interiors of the cylinders.

Referring again to Fig. 3, it may be seen that the cylindrical valve member 11 carries a first vertical side Wall 16 positioned at its left end and a second vertical side Wall 17 positioned at its right end. Abutting flanges 18 and 19 are formed on side walls 16 and 17, respectively, and these flanges cooperate with the ring member 1 and valve member 11 to aid in making the sliding fit between the latter members essentially gas tight. Additionally, the abutting flanges serve to axially position the cylinders 2 on the valve member 11. Abutting flange 18 is provided with a plurality of ducts 20 which are in communication with the intake ducts formed on valve member 11. The ducts 20 may be connected, by conduits to a carburetor arrangement (not shown) for providing a supply of a combustible gas mixture to the combustion chamber.

Returning now to the actuating means for causing controlled reciprocatory motion of the pistons, a plurality of arcuate segment gears are positioned in circumferential spaced apart relation about each of the side walls 16 and 17. Two of the segment gears may be more clearly seen at 21 and 22 of Fig. 1. Each of the gears 21 and 22 have teeth 23 projecting radially outwardly as shown in Fig. 2. Additionally, a plurality of arcuate segment cams are also positioned in circumferential spaced relationship about each of the side walls 16 and 17. Two of the segment cams may be clearly seen at 24 and 25 of Fig. 1. Each of the segment cams have contoured surfaces on their radially inward side as shown generally at-26 in Fig. 4. It should be noted that the gears and cams are circumferentially staggered on the side walls and that there is a set of inlet and exhaust ducts for each gear and cam pair 50 that rotation of a cylinder past a gear and a cam will also pass the cylinder over an inlet and an exhaust duct on the valve member.

In order to effect controlled reciprocation of the piston 3, gear wheels 9 and the arcuate segment gears are arranged to mesh and cause rotation of the crank 6 when the cylinder carrying ringmember 1 is rotating through predetermined portions of a revolution. At other times during a single revolution of the cylinder carrying ring member 1, the gear' wheels 9 are disengaged from the arcuate segment gears and cam follower pins 10 are engaged with the radially inward contoured cam surfaces 26 of the arcuate segment cams. Assuming that the cylinder 2, of Fig. 1, is rotating in a counterclockwise direction, the cam follower pin 10 associated with that cylinder is then riding on the radially inward contoured cam surface 26 of segment cam 24 and, due to the contour of the cam, the piston 3 is at its bottom dead center position after having completed a compression and discharge stroke. As the cylinder 2 moves counter-clockwise, the gear wheel 9 associated with the cylinder engages segment gear 22 and the cam follower pin 10 slides off of segment cam 24. Further rotational movement of the cylinder causes the gear wheel 9 to rotate as it passes over segment gear 22 and this in turn results in a raising of the piston 3 through its intake stroke. During the intake stroke, the intake duct 13 is in communication with the interior of the cylinder and a combustible mixture is drawn into the cylinder. When the piston 3 reaches its top dead center position the rotation of the cylinder covers the intake duct 13 and, as the piston starts to descend due to the segment gear 22 and gear wheel 9 interaction, the compression and discharge stroke begins.

The arcuate length of the segment gear 22 (and the other segment gears) is determined by the compression ratio desired within the cylinder. As the piston descends towards the desired compression ratio for ignition, the gear wheel 9 rides out of engagement with segment gear 22 and cam follower pin 10 simultaneously becomes engaged with segment cam 24. Further rotation of the cylinder results in reciprocatory movement of piston 3 in accordance with the contoured inward surface 26 of segment cam 24. The surface 26, as shown in Fig. 4, is provided with a first concentric portion 27, an actuating portion 28, and a second concentric portion 29. While cam follower pin 9 rides on the first concentric portion 27, the piston 3 is held stationary with respect to reciprocatory motion and during this period ignition occurs by firing the spark plug. In conjunction with the ignition of the combustible mixture and rapid rise in pressure and temperature, the exhaust duct 15 becomes uncovered by the cylinder 2. The synchronization is such that, as the pressure builds up in the cylinder, the exhaust duct progressively opens wider thereby limiting the pressure and temperature rise in the cylinder. With the uncovering of the exhaust duct 15, the exhaust gases are directed through this duct at the radial gas turbine wheel buckets 30 and thereby provide power to the turbine wheel. As the exhaust duct 15 is fully opened and the pressure begins to drop off in the cylinder, the rotary movement of the cylinder carries cam follower pin 9 onto the actuating portion 28 of segment cam 24. The actuating portion of the cam then moves the piston down towards its bottom dead center position, thereby expelling all of the exhaust gases from the cylinder and bringing the cam follower pin to the second concentric portion '29 of the segment cam 24. On this portion, the piston has completed one full cycle and is held at bottom dead center while the cylinder rotates to bring the gear wheel into contact with the next segment gear in order to start a new cycle.

Referring to Figs. 5 and 6 wherein the intake and exhaust ducts are shown in greater detail, it may be seen that cooling means maybe used with the exhaust ducting to lower the temperature of the exhaust gases and cool the valve member 11. Conduits 31 and 32, which may receive a cooling fluid from a source (not shown) are formed. adjacent to exhaust ducts 14. Conduit 31 is connected with the lower portion of exhaust duct 14 by means of a plurality of parallel passageways 33 and conduit 32 is connected with the upper portion of ex haust duct 14 by means of a plurality of parallel passageways 34. By controlling the flow of cooling fluid through conduits 31 and 32 into the exhaust duct, the temperature of the exhaust gas may be controlled and the high temperature region of the valve member may be cooled with a minimum loss of power since the heat I 5, given up to the cooling fiuidis utilized by subsequent expansion in the gas turbine. I

As shown in Fig. 6, exhaust duct 14 passes completely through valve member 11 and has a converging cross section. This arrangement provides a nozzle effect and, In conjunction with the controlled reciprocation of the piston during and immediately after ignition, the exhaust gas stream is smoothed out over a relatively long period of time to provide a steady power input to the turbine rather than an intermittent series of high energy pulses. It is further apparent that during the time when exhaust gases are leaving the'cylinder, a reactive force is applied against the cylinder tending to cause rotation in a direction opposite to that of the turbine. This reactive force may be utilized to overcome the frictional forces involved in rotating the cylinders and frictional forces involved in rotating the cylinders and driving the pistons and, additionally, the cylinders may be geared to the turbine wheel to utilize any excess power developed over that which is necessary to overcome friction and drive the pistons through their reciprocatory cycles.

Fig. 7 shows an arrangement wherein the excess power developed by the reactive forces in the cylinder may be utilized. A ring gear 35 is shown mounted to the cylinders 2. Upon rotation of the cylinders the ring gear drives an intermediate gear 36 which is mounted at one end of shaft 37. Shaft 37 is supported by bearing 38 and carries a second intermediate gear 39 at its other end. Gear 39 in turn meshes with a second ring gear 30 which is mounted on turbine wheel 41. Thus, any power developed in excess of the needs of the rotating cylinders may be added to the power output developed in the turbine wheel. Additionally, for starting purposes, the turbine wheel may be driven by any convenient starting engine known to the art and the gear connections to the cylinders will cause them to rotate until sufficient speed is obtained for the engine to become selfsustaining.

As the means used to fire the spark plugs form no part of this invention, no detailed discussion concerning its operation will be included; however, one arrangement will be briefly discussed. A conventional battery and ignition coil may be used in conjunction with a plurality of contacts on both the rotating cylinders and a stationary side wall. The contacts would replace the conventional distributor and may be arranged so that there is a stationary contact adjacent to and radially in line with the first concentric portion 27 of each cam and a moving contact fastened to each cylinder which is radially in line with the centerline of each crank 6. In this manner, by-

proper positioning of the stationary contact, ignition may be obtained while each piston is under the control of the first concentric portion 27 of a segment cam.

It is of interest to note that this rotary combustion chamber provides a great number of ignitions per revolution of the cylinder carrying ring member. In the disclosed embodiment, eight cylinders are carried by the rotating ring member and six sets of piston actuators and valve ducts are carried by the stationary valve member. For each revolution of the ring member, each cylinder will go through six complete cycles and provide controlled power surges to the turbine. Since there are eight cylinders on the ring member, there will be forty-eight power surges in all per revolution of the ring member. It is apparent that with this high ignition rate and controlled exhaust arrangement, a greatly improved source of exhaust gases is provided for gas turbine usage. Additionally, the weight to horsepower ratio of this engine is obviously considerably improved over prior rotary combustion arrangements.

It is also of interest to note that the controlled exhausting of gases from the cylinders, rotation of the cylinders in open air, and provision for injecting cooling water into the exhaust stream allow for minimizing the deleterious efiects of high temperature operation that occurred in earlier forms of engines of this type. The arrangement described, since it operates at relatively low pressures and temperatures, does not require expensive special materials with their attendant high costs.

It will be apparent to those skilled in the art that many modifications of the preferred embodiment may be utilized. A number of the more important ones will now be listed. Instead of rotating the cylinder carrying ring member 1 and holding the valve member -11 stationary, the ring member may be held stationary and the valve member may be rotated to achieve exactly the same.

sequence of operation. Additionally, rather than utilizing separate ignition means, the compression ratio may be selected high enough to utilize a fuel injection arrangement with self-ignition similar to that utilized in diesel engines. Further, the rotary combustion chamber is not limited for use only with a radial flow type gas turbine, but may be used with an axial flow turbine by providing additional exhaust ducting. Finally, the positions of the ring member 1 and valve member 11 may be inverted and the cylinders may be arranged to rotate within the valve member rather than about it.

While I have shown and described a particular embodiment of my invention and discussed various major modifications that might be made, it will be obvious to those skilled in the art that various other changes and modifications may be made without departing from my invention in its broader aspect, and I, therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

I claim:

1. The combustion apparatus for an exhaust gas turbine comprising a first member; a plurality of cylinders carried by said first member, said cylinders each having a piston mounted for reciprocation therein; a second member positioned adjacent to said first member, said second member having a plurality of intake and exhaust ducts formed therein; means for rotating one of said members relative to the other; and actuating means for reciprocating each of said pistons in timed relationship with the relative rotary motion of said members, said actuating means comprising gear means for reciprocating each of said pistons through a major portion of a full reciprocatory cycle, and cam means operable to complete the reciprocatory cycle, said cam means being operatively in control of said pistons during the time when the exhaust ducts of said second member are in communication with said cylinders.

2. The combination of claim 1 wherein said cylinders are open ended and said second member cooperates with each of the cylinders and pistons to therewith form a chamber.

3. The combination of claim 1 wherein said means for rotating one of said members relative to the other includes a reactive force resulting from the flow of exhaust gases through said exhaust duct.

4. The combination of claim 1 wherein said second member is stationary and said first member rotates about said second member. 7

5. The combination of claim 1 wherein conduit means are provided in communication with said exhaust ducts for introducing a coolant into said exhaust ducts.

6. Combustion apparatus for an exhaust gas turbine comprising a cylindrical rotary ring member; a plurality of radially disposed cylinders positioned about the periphery of said ring member, said cylinders each having a piston mounted for reciprocation therein; a cylindrical stationary valve member positioned adjacent to and internally of said ring member, said members being in tight sliding contact with each other, said valve member having a plurality of sets of intake and exhaust ducts formed therein; a plurality of arcuate gear segments fixed to said valve member, said gear segments being circumferentially spaced apart from each other; a plurality of cams fixed to said valve member, said c amsbein g circumferentially spaced apartfrorn each other, therebein g a corresponding gear's egment and cam for each setof intake and exhaust ducts; a plurality of gear Wheels mounted on said ring member for engagement With said gear segments; a plurality off cranl; means mounted on said ring member, each of said gran}; means operatively connecting one of sa dasa Whe ls wit n Q an pistons; h form; t lting said ring member; and means carried by said gear wheels for engaging said cams during a portion of the reciprocatory cycle of ,each piston to control the reciprocatory motion of the piston when an exhaust duct is in communication with a cylinder.

7 The combination of claim '6 which further includes conduit meansmeomm nimion with said exhaust ducts for introducing a coolant into said exhaust ducts.

References Cited in the file of this patent UNITED STATES PATENTS 329 238 M M y 8, 9 6 1,583,560 Morris May 4, 1926 2,212,283 Weeks Aug. 20, 1940 2 ,273,025 Dillstfom Feb. 17, 1942 

